Subject: Re: [homenet] I-D Action: draft-ietf-homenet-hncp-06.txt

From: Markus Stenberg <[email-masked]>
Date: Thu, 2 Jul 2015 09:38:34 +0300

On 27.6.2015 2.49, Juliusz Chroboczek wrote:
>> "  If the considered delegated prefix is an IPv6 prefix, and whenever
>>    there is at least one available prefix of length 64, a prefix of
>>    length 64 MUST be selected unless configured otherwise by an
>>    administrator.  In case no prefix of length 64 would be available, a
>>    longer prefix MAY be selected."
> Well spotted, thanks.  Markus, would you be open to relaxing the MUST, 
> and adding a guideline about which of the available /64s is suitable 
> for carving up?
I reworded the current text as such, as I consider it sane:

    If the considered delegated prefix is an IPv6 prefix, and whenever
    there is at least one available prefix of length 64, a prefix of
    length 64 MUST be selected unless configured otherwise.  In case no
    prefix of length 64 would be available, a longer prefix MAY be
    selected even without configuration.

It does not exactly say _what_ configuration (whether provided by 
administrator, or some other process such as autonomic stuff); but by 
default, HNCP implementation MUST use /64.

Obviously, this may not be the final word if my coauthors step in or 
someone provides better language to describe the intent. I do not think 
SHOULD is good idea when describing the non-configured default which 
99+% of home routers should be doing.

Cheers,

-Markus